The present invention relates to an air jigging machine for the dry separation or processing of raw materials, especially coal, and includes a material-feeding mechanism, at least one jigging-material carrier that is provided with openings, as well as a discharge device for the heavy material and the light material that are layered upon the jigging-material carrier during the separating process, whereby for the loosening up or aerating, and for the layering, of the material supplied to the jigging-material carrier into a heavy material layer, which acts as a jig bed, and a light material layer disposed thereupon, an air flow, as working air, supplied from an air funnel disposed below the jigging-material carrier, flows through the jigging-material carrier; the air flow is composed of a partial stream that constantly flows through the jigging-material carrier, and a pulsating partial stream that is superimposed thereon.
An air jigging machine having the aforementioned features is described, for example, in DE 20 2005 007 472 U1. The material that is to be processed is supplied via a material-feeding device to the single jigging-material carrier, which is embodied, for example, as a perforated plate, or is comprised of a wire mesh. By means of an air funnel disposed below the jigging-material carrier an air stream is supplied that is comprised of a partial stream that flows constantly through the jigging-material carrier, and a pulsating partial stream that is superimposed on the constant partial stream. As a consequence of the supply of the constant air stream to the jigging-material carrier and the material that is to be processed disposed thereon, a basic fluidization of the material disposed on the jigging-material carrier is achieved, so that therewith to a certain extent permanent loosening of the material is obtained that initially has a relatively low pressure loss as the working air flows vertically through the jigging-material carrier. Thus, with regard to the superimposed pulsating air stream, a relatively small volume flow of pulsed air is required in order within the framework of the process control immanent to an air jigging machine to periodically raise and lower the material bed disposed on the jigging-material carrier, and to thereby bring about the layering of the materials into a heavy material layer and a light material layer disposed thereon. The working air that flows through the jigging-material carrier is captured above the jig bed in a housing that encloses the jigging-material carrier, and is guided as exhaust air over a filter unit.
The known air jigging machine has the drawback of a limited capacity, since the surface of the jigging-material carrier cannot be arbitrarily increased.
A wet jigging machine having an increased capacity is described in DE-A-172 178. With this jigging machine, which is operated with a pulsating water flow, two jigging-material carriers are disposed over one another and through which flows the water that is located in a settling tank disposed below the lower jigging-material carrier, and that is caused to pulsate. Extending through the lower jigging-material carrier is a tubular member that is connected to the settling tank, so that the travel of the pulsating water can pass over the upper jigging-material carrier. The upper jigging-material carrier is furthermore also penetrated by a tubular member in order to be able to compensate for excess water buoyancy.
It is an object of the present invention to also design an air jigging machine having the aforementioned general features in such a way that its processing capacity is increased.